We fix what's broken, fast, and we don't disappear after the invoice. Emergency dispatch available across Mount Prospect and the surrounding zip codes.
Our Mount Prospect dispatcher asks a few quick questions to gauge urgency and get you the fastest available window.
You'll get a flat-rate quote before any repair work begins — no guessing what the final bill will look like.
If anything feels off after we leave, a follow-up call gets a technician back out to make it right.
Leonard HVAC was built by technicians who got tired of watching homeowners get oversold. Every technician we send to your door is background-checked, factory-trained, and licensed to work on the systems installed throughout Mount Prospect, IL.
You won't find us buried under layers of call-center scripts — we're the crew that answers the phone at 2am when your furnace quits in the middle of a cold snap. We carry the credentials Mount Prospect inspectors and property managers expect to see, and we keep that documentation available on request for every job, residential or commercial.
Being local matters more than most companies let on. That local knowledge shapes how we diagnose problems — it's the difference between a tech who's guessing and a tech who's seen your exact situation a hundred times before.
Trust in this industry gets eroded fast, and it takes real consistency to earn it back. That's the gap we built Leonard HVAC to close. Every dispatcher, every technician, and every follow-up call is held to the same standard, because a customer who trusts us once tends to call us again — and Mount Prospect is a small enough community that reputation travels fast.
That local context saves time on every call, because we're not starting from zero on basic questions about your neighborhood or your system. We keep parts inventory stocked based on what actually fails most often on Mount Prospect's housing stock.
Every service below is backed by the same licensing, warranty, and upfront pricing you get on any job we run.
Breakdowns rarely happen at a convenient time, which is exactly why our emergency line runs 24 hours a day. Our Mount Prospect dispatch team moves emergency tickets to the front of the schedule so a technician is diagnosing your system as fast as physically possible.
Once a technician is on-site, the goal is always a same-visit repair — most emergency calls in Mount Prospect get resolved in a single trip, not a multi-day back-and-forth.
If your unit is past its expected service life, running loud, or spiking your utility bill, a replacement conversation is worth having. We walk Mount Prospect homeowners through efficiency ratings and how they translate into real monthly savings before a single piece of equipment gets ordered.
Most installs in Mount Prospect are completed in a single day, and we walk you through the new thermostat and any app controls before we leave.
A retail floor, a restaurant kitchen, or an office suite can't run without stable climate control. Our commercial division services light industrial and warehouse ventilation across Mount Prospect, with service agreements built around your operating hours.
Our commercial techs are trained to work around your customers and staff, scheduling noisy or disruptive work outside peak hours whenever possible.
Most emergency breakdowns start as a small, ignorable warning sign months earlier. Beyond standard tune-ups, we also handle duct cleaning and sealing to stop conditioned air from leaking into attics and crawlspaces for Mount Prospect households that want more than just temperature control.
A tune-up typically takes under an hour and covers the checkpoints most likely to catch a problem before it becomes a breakdown.
This is the standard every Mount Prospect technician on our team is held to.
If the same issue returns within the warranty period, we come back and fix it at no additional labor cost.
Emergency dispatch never comes with a hidden surcharge sprung on you after the fact.
A technician doesn't consider the job done until the system is tested and performing correctly.
Catching these signs early usually means a same-day repair instead of an emergency call at the worst possible moment.
A healthy system runs with a consistent, low hum — banging, screeching, or grinding usually points to a loose part or failing motor.
This is one of the most common complaints we hear on service calls across Mount Prospect.
Gradual efficiency loss is easy to miss month to month, but it adds up fast over a season.
This is one of the warning signs we recommend not waiting on.
A musty smell often points to mold or moisture buildup somewhere in the ductwork.
We'll always tell you honestly when a repair is the better call versus when it isn't.
We explain diagnostic fees and repair estimates before authorizing work.
Emergency calls get moved to the front of the line automatically.
If something isn't right after we leave, we come back and make it right.
Every technician carries current state licensing and manufacturer training.
Photos and plain-language notes accompany every diagnostic.
We'll walk you through what's actually available before you decide.
A snapshot of the feedback that keeps us accountable.
"The furnace stopped working overnight and someone was at our door before 9am. No pressure to buy a whole new system when a repair was all we needed."
"Signed up for the annual plan after our first repair and it's paid for itself already. You can tell these guys actually know what they're doing."
"Had a full system replacement done and it was the smoothest home project I've had in years. Would recommend to anyone in Mount Prospect needing a real replacement, not a patch job."
"Our restaurant's rooftop unit went down on a Friday night and they had someone out fast. Now our go-to for every property in the portfolio."
"The estimate matched the final invoice exactly, down to the dollar. Installation crew was in and out in a day and left the space cleaner than they found it."
"Diagnosed a failed capacitor and had it swapped within the hour. Genuinely relieved to have found a crew that answers when it matters."
Understanding what typically fails helps homeowners know what to watch for and when a repair call is worth making before things get worse.
The shift between peak heating and peak cooling demand is exactly when older or neglected equipment tends to fail. Before the heaviest cooling months hit, it's worth having the refrigerant charge checked, the condenser coils cleaned, and the filter replaced — all of which directly affect how hard the compressor has to work.
Setting a programmable or smart thermostat to a consistent schedule reduces the number of times the system has to work hard to catch up to a big temperature swing. None of this replaces a professional tune-up, but it does reduce the wear that leads to premature breakdowns between visits.
Whether your Mount Prospect home has a traditional split system, a ductless mini-split, a heat pump, or a hybrid dual-fuel setup, our crews are equipped to diagnose and repair it. If your system was installed by a different company entirely, that's not a problem — we service equipment regardless of who originally put it in, and we'll pull the model and serial information to confirm parts compatibility before any repair begins.
Here's a look at the kind of experience that shows up at your door.
Handles the majority of Mount Prospect installs and specializes in properly sizing equipment for older housing stock.
Known for fast, accurate diagnostics on no-heat and no-cool breakdowns.
Experienced with the light industrial and retail equipment common across the area.
Because our trucks are staged near Mount Prospect, average arrival windows run faster than what national chains typically offer.
We explain the diagnostic fee upfront and provide a flat-rate repair quote once the issue is identified.
Yes, no-heat and no-cool situations are treated as priority calls regardless of the hour.
Every technician we send is licensed in accordance with Mount Prospect, IL requirements and carries full liability coverage.
As a general guideline, if a system is past 12-15 years old and facing a costly repair, replacement often makes more financial sense.
Plan members typically see fewer surprise breakdowns because small issues get caught during routine visits.
We cover Mount Prospect and the surrounding communities, including the zip codes listed in our coverage section below.
Our commercial team handles rooftop units, multi-zone systems, and facility contracts alongside our standard residential repair work.
Yes, we service systems regardless of who originally installed them.
We understand a full system replacement is a significant expense, which is why flexible payment options exist.
Most Mount Prospect homes benefit from two tune-ups a year — one before cooling season and one before heating season.
Beyond basic safety checks, it's best to leave diagnosis to a licensed technician rather than attempting a repair yourself.
Ask about current after-hours rates when you call +1-866-805-8548.
Most standard repairs are completed in under two hours once the technician has diagnosed the issue and you've approved the quote.
For most residential visits, yes, an adult should be present to grant access and approve any quoted work.
Housing stock varies a lot across Mount Prospect — older homes often still run original ductwork that needs different care than the sealed, high-efficiency systems going into newer builds.
We also work regularly with homeowners associations, property management companies, and multi-unit buildings throughout Mount Prospect.
A full system replacement is one of the bigger home expenses most people face, and we don't expect everyone to pay it in a single lump sum. If a rebate or local incentive program applies to your Mount Prospect installation, our technicians will flag it during the estimate rather than leaving you to track it down after the fact.
If your address falls within Mount Prospect, IL and near Mount Prospect, there's a strong chance we already service your street.
Property managers with multiple Mount Prospect addresses can consolidate everything under one account for simpler scheduling and consistent pricing across every location.
